Blue roofs can be used in combination with [[green roofs]] by employing a scaffold system to keep the vegetation rooting layer out of the ponded water. Blue roofs could also be employed in combination with a [[rainwater harvesting]] system which had daily usage demand. This could offset some part of the cistern capacity.
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Blue roofs can be used in combination with [[green roofs]] by employing a scaffold system to keep the vegetation rooting layer out of the ponded water. Blue roofs could also be employed in combination with a [[rainwater harvesting]] system which had daily usage demand. This could offset some part of the cistern capacity.